TheSamba.com :: View topic - Cold Start injector switch to dash

Thu Apr 28, 2016 3:21 am

Hi Guys,

How easy is it to bypass the thermo time switch and wire the Cold start injector directly to a switch on the dash board?

Is it just a case of running a wire from a dash switch to one terminal on the CSI and the other one to ground ?

Just after temporary fix till I get a new time switch sorted so I can start the thing in the morning.

Thanks

Nost

Thu Apr 28, 2016 3:44 am

It is just an electric solenoid which opens a fuel valve.
Sure, manual operation can be wired in, though not advised but in an emergency.......

The thermo time switch makes or breaks ground.

Dave

Thu Apr 28, 2016 5:28 am

What rig are we talking about here? Can we assume an air cooled? The system is pretty dependable and most don't have a problem with it. Maybe you have some other problem that needs correction?

Thu Apr 28, 2016 5:40 am

Wildthings wrote: What rig are we talking about here? Can we assume an air cooled? The system is pretty dependable and most don't have a problem with it. Maybe you have some other problem that needs correction?

Aircooled LJet

1. Start perfectly from cold every time.
2. When warm/hot cranks over for around 8 seconds before starting
3. When cold start injector is disconnected engine starts first turn of the key when warm/hot.
4. Guessing it's thermo time switch as 9 out of 10 fires in at the 8 second mark when warm, thermo time switch is telling the CIS to spray every time regardless of cold,warm or hot.

Is it fair to assume based on the above its the thermo time switch?

Thu Apr 28, 2016 9:13 am

Sounds correct! ^^^^

Too much hot start gasoline.

Dave

Thu Apr 28, 2016 9:20 am

Noster wrote:

1. Start perfectly from cold every time.
2. When warm/hot cranks over for around 8 seconds before starting
3. When cold start injector is disconnected engine starts first turn of the key when warm/hot.
4. Guessing it's thermo time switch as 9 out of 10 fires in at the 8 second mark when warm, thermo time switch is telling the CIS to spray every time regardless of cold,warm or hot.

Is it fair to assume based on the above its the thermo time switch?

I would say so as the thermotime switch shouldn't be activated even monentarily above around 100° F, IIRC. Have you tried replacing the TTS switch? It is also possible that someone has messed with the wiring to the switch.

At one time it wasn't uncommon to find that people had added a push button to the dash to operate the CSV and even a rheostat to change the effective output of the TSII sensor particularly if they used their vehicles over a wide range of elevations, say to go skiing in Colorado.

Thu Apr 28, 2016 9:22 am

on my d-jet car i found that i did not need the cold start injection during the summer .

Thu Apr 28, 2016 12:03 pm

You will want to use a push button momentary type switch. It is easy to get distracted and leave a toggle on. VW had a lot of problems with Hot Start on their CIS cars. Their work around was a pulse relay you added that would pulse the cold start valve during cranking. A T/S relay will not work. I see the pulse relays from time to time, but I don't think you can get them from the dealer any more. It was a complete service kit. Harness number 171 971 764C and the relay is 813 906 064.

I would suggest putting a fuel pressure gauge on the engine. Often, fuel pressure leaks down and cause a hot start problem. The cold start valve could be masking the problem. Anyhow good luck.

Thu Apr 28, 2016 1:02 pm

MarkWard wrote: VW had a lot of problems with Hot Start on their CIS cars. Their work around was a pulse relay you added that would pulse the cold start valve during cranking.

By 1980, the hot-start pulse relay was standard equipment (i.e. factory installed) on CIS cars. Every CIS Rabbit, Cabriolet, Jetta, Scirocco, Golf of the '80s will have that relay (marked 37) in the panel.

The retrofit kit was dropped from VW's catalog in 1988.

Sun May 01, 2016 9:01 am

New thermo time switch installed, all sorted perfect hot starts :D

Sun May 01, 2016 9:09 am

Noster wrote: New thermo time switch installed, all sorted perfect hot starts :D

Good, the TTS's seem to change settings as they age until one day the engine will not start any more. They are probably only good for 100K miles or 10 years.

Sun May 01, 2016 3:10 pm

Noster wrote: New thermo time switch installed, all sorted perfect hot starts :D

way to go. was your old switch repairable? I have cut them open and cleaned up corroded contaxts and got them working again. rmay fix you old on to save as an emergency spare.